The first step in a successful endodontic treatment is to gain access to the pulp chamber and find all of the canals. To achieve this goal, practitioners need to be familiar with all possible variations of the root canal and have adequate information of the tooth needing treatment. The present case report describes an anatomical variant of the maxillary second molar with 6 canals, a variation that has not been previously reported. Helpful hints for detection of the unusual canal are presented, as well. Keywords: maxillary second molar, root canal, root canal variation